It has been known in arthroscopic surgical procedures, to enter a surgical site, for example a knee joint, with an elongate entry tool, such as a trocar, sheathed in a snug fitting outer sleeve. Thereafter the entry tool is removed, leaving the entry end of the sleeve at the surgical site and the other end of the sleeve protruding from the patient. Thereafter, one or more additional elongate surgical tools, such as an arthroscope or obturator can, in desired sequence, be alternately inserted through the sleeve to reach the surgical site.
Further, it is known to equip the sleeve for connection to an irrigation liquid source for injecting irrigation liquid therethrough into the surgical site, and for connection to a suction source for removing flowable material from the surgical site.
In each instance, the sleeve, extending into the surgical site, acts as a conduit of access to the surgical site from outside the body of the patient and permits a variety of surgical procedures to be performed without requiring more than the very small incision needed to insert the sleeve.
In prior devices of this type, the outer end of the sleeve is provided with a manually actuable locking device engageable with a connector on the tool for at least axially fixing the tool within the sleeve. However, prior locking devices of which I am aware have not been entirely satisfactory.
In one such prior locking device, a threaded member must be rotated with respect to the sleeve to lock and unlock a tool with respect to the sleeve. However, some surgeons have confused the lock and unlock rotation directions. Further, the threaded member may become slippery during surgery and require extra care to lock and unlock. Further, a surgeon may fail to fully rotate the threaded member and thus need to repeat the rotation.
Accordingly, the objects and purposes of this invention include provision of a locking device for axially releasably locating an inner surgical tool within an outer sleeve, in which it is intended to improve upon prior locking devices, in which locking and unlocking of the tool with respect to the sleeve can be done with one hand, in which locking and unlocking require distinctively different kinds of manipulation and can readily be done without significant training by surgical personnel and despite the presence of liquids or slippery materials on the tool and sleeve, in which the locking is positive and will retain a tool in the sleeve despite feeding of liquid under pressure into a space between the sleeve and tool and toward the wound and despite possible liquid pressure tending to push the tool outwardly out of the sleeve.
Further objects and purposes of the invention will be apparent to persons acquainted with apparatus of this general type upon reading the following specification and inspecting the accompanying drawings.